Optimistic DRX for Machine-Type Communications in LTE-A Network

In long-term evolution-advanced (LTE-A) network, the third-generation partnership project has proposed machine-type communications (MTC) as a new paradigm where devices transfer data among themselves with limited human interaction. For devices in MTC, power saving has become an important issue because many devices are powered by battery. In LTE-A network, the standard power saving mechanism, called discontinuous reception (DRX), is designed for normal mobile users, not for MTC devices. In this paper, we propose an optimistic DRX (ODRX) mechanism to be suitable for MTC devices. ODRX considers the radio resource control connection release and re-establishment to save more power. We also introduce the optimistic flag to allow longer sleep periods. Analytical and simulation models are proposed to investigate the performance of ODRX, and ODRX is then compared with the standard DRX and dynamic DRX (DDRX) through simulation experiments. The results show that ODRX outperforms standard DRX and DDRX by gaining significant extra power saving with little extra wake up latency. We also propose guidelines to configure ODRX parameters.